In an imaging device, such as a digital camera, it is known that a photographed image is distorted by the distortion of the photographing optical system. This is due to the difference of imaging magnification between the center portion and edge portion of an image, and in the photographing optical system, a pin cushion distortion is generated in photographing in the telephoto state, and a barrel distortion is generated in photographing in the wide angle state. Digital cameras, on the other hand, have characteristics to acquire images as digital data, and various technologies to correct distortion by performing image processing (digital processing) on the image data have been proposed (e.g. see Japanese Patent Application Laid-Open NO. 2008-99184). Thereby the user can acquire photographed images with less distortion.